FORMLABS WHITE PAPER: Introduction to Digital …...FORMLABS WHITE PAPER: Introduction to Digital Dentistry and 3D Printer Buyer’s Guide 6 The digital dentistry workflow can move

January 2018 | formlabs.com

FORMLABS WHITE PAPER:

Introduction to Digital Dentistry and 3D Printer Buyer’s Guide

Learn how to move from analog to digital workflows

and find a 3D printer for your dental practice or lab.

FORMLABS WHITE PAPER: Introduction to Digital Dentistry and 3D Printer Buyer’s Guide 2

Table of Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Why Go Digital? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

The Digital Dentistry Workflow . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

How to Implement Digital Workflows in a Dental Lab or Practice . . . . . . . . 8

Dental 3D Printing Technologies . . . . . . . . . . . . . . . . . . . . . . . . . 10

How to Evaluate 3D Printing Solutions . . . . . . . . . . . . . . . . . . . . . . . 12

Get Started with Digital Dentistry and 3D Printing. . . . . . . . . . . . . . . . . 16


IntroductionThere’s no way around it: the future of dentistry is inevitably digital. With cutting-edge digital

solutions for impression scanning, treatment planning, and digital manufacturing, what was

once prohibitively expensive is rapidly becoming accessible, already transforming thousands

of dental labs and practices worldwide. As CAD/CAM continues to replace traditional

workflows and become the standard of care, digital solutions have become a necessary

consideration for any dental business.

Throughout this white paper, you’ll learn about:

The reasons and benefits of going digital

The digital dentistry workflow and how it’s different from analog processes

The best strategies for getting started with digital dentistry

Differences between dental 3D printing technologies

The comprehensive criteria and aspects to evaluate before investing

in a 3D printing solution

If you are managing a dental laboratory or practice, look no further—this is your ultimate guide

to digital dentistry.

Why Go Digital?HIGH QUALITY AND PRECISION

No two dental cases are the same. Patient anatomy is unique, and each treatment is tailored,

enabled by a long history of artisanal custom, human-centric craftsmanship. But, as with any

trade, quality is dependent on the skills of a given dentist, assistant, or technician, and achieving

consistent, high-quality, affordable dental products with so many potential sources of error is

incredibly difficult.

Digital dentistry reduces the risks and uncertainties introduced by human factors, providing higher

consistency, accuracy, and precision at every stage of the workflow. Intraoral digital impression

scanning removes many of the variables associated with taking a traditional impression, giving

technicians more accurate data to design from. Dental CAD software tools provide visual interfaces

similar to traditional workflows, with the added benefits of being able to automate certain steps,

as well as easily identify and fix mistakes. Digital manufacturing equipment such as 3D printers or

milling machines deliver a range of high-quality custom products and appliances with superior fit

and repeatable results.

All of this makes for dental products with better fit, function, and clinical acceptance by the patient,

with fewer errors and adjustments along the way.


IMPROVED EFFICIENCY: TIME AND COST SAVINGS

Digital dentistry can be a no-nonsense business choice, improving efficiency in dental procedures

and streamlining workflows, benefiting both the dental practice and dental lab.

In a dental practice, saving time on menial tasks means shorter appointments, increased

throughput, and happier patients. Easy impression taking with intraoral scanners reduces chair time,

and cuts out the cost of impression materials, or the need to ship impressions to the lab. There’s

instant feedback, and no manual errors like voids, bubbles, or tears, eliminating the need for

retakes. Practices can bring production in-house for simple applications using 3D printers, saving

both time and costs.

In the dental lab, digital design and manufacturing increase technician productivity, and reduce

hands-on work, leading to more precise production, fewer reworks, and less time per unit. CAD

software now includes tooth and implant libraries, and application-specific suites simplify the design

and planning of any restoration or appliance. Milling machines and 3D printers can batch jobs

together, operate unattended, and are now so affordably priced that dental labs of any size can

take advantage.

3D printed removable die models are an efficient way to check the accuracy of final restorations.


BETTER PATIENT EXPERIENCE AND OUTCOMES

One of the most significant benefits of digital technologies is improved patient experience and

comfort. A satisfied patient is more likely to come back and refer others, contributing to the long-

term success of all dental businesses.

Digital technologies improve the workflow from diagnosis to planning to treatment. Intraoral

scanning is faster and substantially more comfortable than regular impressions, while CBCT

scanning adds a new dataset to assist planning. Virtual treatment planning and appliance design

enable less invasive treatments and prosthetics with a better fit.

Digital dentistry makes for faster treatments, fewer visits, and higher prosthetic acceptance rates

with measurably better clinical outcomes.

3D printed surgical guides enable quick and high-precision implant placement for just $2-5 per guide.


The digital dentistry workflow can move back and forth between

dental practice and lab, increasing efficiency and collaboration.

The Digital Dentistry WorkflowWith a wide range of digital dental specialties, from general dentistry to orthodontics and

implantology, the design of different treatments and prostheses varies somewhat by specialty and

application, but they all follow the same basic digital workflow: 1. Scan, 2. Design, 3. Manufacture.


SCAN

Like traditional dental product fabrication, digital production starts with the patient’s individual

anatomy. Intraoral scanners can be used in the dental practice to capture scans directly from

the patient, replacing manual impressions with fast and accurate digital impressions. Alternately,

desktop optical scanners in dental labs can be used to scan traditional alginate and PVS

impressions or plaster models. For treatments and applications that require patient osteotomy, such

as surgical guides for implants, an additional dataset needs to be collected using CBCT scanners.

Requirements: Intraoral scanner or desktop optical scanner, CBCT scanner (optional)

DESIGN

After scanning, patient anatomical data is imported into dental CAD software, where treatments can

be planned and prosthetics designed. Most software packages use design processes very similar

to traditional workflows, employing highly visual interfaces with features like virtual articulators that

are familiar to all technicians. Digital design results in easier, more precise treatments and simplified

communication. After the treatments are designed, models can be exported for manufacturing. If a

rework is needed, the same digital design can be reused without additional effort.

Requirements: Dental CAD software

MANUFACTURE

To physically realize a digital model of a dental product, 3D models are uploaded to a digital

manufacturing endpoint, such as a 3D printer or a milling machine. 3D printers are suitable for both

labs and practices, and can produce a variety of products, including dental models, surgical guides,

splints, retainers, wax-ups, castable prosthetics, and dentures. 3D printers work by solidifying parts

layer by layer to form the shape of the dental appliances and models with digital precision. Milling

machines are more common in dental labs, but also have some limited applicability to the dental

practice as well. These can be used to create prosthetics and final restorations by subtracting from

a solid block of material, such as zirconia.

Depending on the particular product, assembly with prefabricated accessories might be necessary.

Professional machinery and advanced materials are essential to manufacture dental products with

a smooth surface finish, fine details, and high precision.

Requirements: 3D printer or milling machine


How to Implement Digital Workflows in a Dental Lab or Practice PICK AN APPLICATION

Transitioning to digital dentistry is best done gradually, shifting application by application to avoid

unnecessary risks. First, choose an application where digital dentistry makes the most sense for

your business. Consider a workflow that’s currently inefficient, unreliable, or expensive—or perhaps

a product that you aren’t currently able to offer to customers.

For dental practices, in-house 3D printing can cut costs and lead times, or enable the use of certain

types of treatments such as guided surgery. Dental models, surgical guides, and splints all have

easy workflows that an assistant can be trained to carry out. Some milling machines also offer in-

practice single-unit crown production, albeit at high upfront cost. Whatever you choose, start with

a single use case and extend to multiple applications, while continuing to rely on labs for complex

cases and milled final restorations.

For dental labs, 3D printers and milling machines offer a variety of digital workflows. Professional

3D printers are incredibly versatile: it’s possible to manufacture a wide range of products, including

restorative models, surgical guides, splints, ortho models, aligners, digital wax-ups, castable

prosthetics, and dentures, on the same machine, just by switching materials. Milling machines offer

solutions for crowns and bridges, splints, full or partial dentures, and more. Each fabrication method

should be considered based on quality and cost-efficiency.

DEFINE AND TEST A DIGITAL WORKFLOW

When you have a specific application in mind, piece together the complete step-by-step digital

workflow for that application to make sure you understand all the pieces needed for 1. Scanning, 2.

Designing, 3. Manufacturing.

For scanning equipment, consider whether your practice will be using intraoral scanners, your

customers will be sending you scan files digitally, or your lab will need a desktop optical scanner to

scan stone models or PVS impressions.

Make sure to get a demonstration of the workflow of any design software to understand the step-

by-step process before adopting it. Then, select a software package compatible with the scanning

and manufacturing equipment of your choice. The easiest way to do this is to stick with software

that allows open importing of scan files, and open .STL export for manufacturing.

When considering manufacturing equipment such as milling machines or 3D printers, always

source samples before buying equipment. Technical data and marketing specs can be misleading

and hard to decipher. Instead of comparing sales brochures, compare actual parts—don’t hesitate

to ask for a physical sample of a milled crown, a 3D printed splint, or whatever you’re considering.

There’s no better way to compare quality between two machines than holding the final product in

your hand.


START SMALL AND SCALE UP

Once you’re ready to start, trial the workflow for a few weeks before going to full production,

leaving time to learn each step and iron out any wrinkles. As you get comfortable with the results,

it’s time to switch the workflow fully to digital, and start scaling up.

In digital workflows, scaling up is a simple matter of adding scanning, design, or production

capacity, depending on where bottlenecks appear. The recent advent of industrial-grade desktop

3D printers offers more production flexibility than ever before, with small affordable machines

enabling labs and practices to add capacity as needed. Having multiple machines brings the added

benefit of fault redundancy, a significant advantage over larger systems.

Offering a new product or service doesn’t have to be a difficult decision with a long-term return on

investment. With digital, businesses can start small, see faster returns on investment, and scale up

over time.


Dental 3D Printing TechnologiesAdditive manufacturing is making digital dentistry a no-nonsense business choice, combining high

quality and improved patient care with low unit costs and streamlined workflows. The market has

been expanding rapidly, bringing this technology within reach for more businesses.

With this expansion, which technologies are relevant for dentistry?

Today, three 3D printing technologies are common in dentistry: stereolithography (SLA), digital light

processing (DLP), and material jetting. Each technology can deliver the precision and accuracy

needed for dental applications, but quality can vary among different machines and systems. Spend

the time to understand each technology, but remember that it’s more important to evaluate specific

equipment, judging based on part quality, ease of use, reliability, and cost.

STEREOLITHOGRAPHY (SLA)

In stereolithography, a vat of liquid resin is selectively exposed to a laser beam across the print

area, solidifying resin in specific areas. Stereolithography is highly accurate and has the best

surface finish of the three technologies. SLA printers offer large build volumes and a wide range of

materials for various applications. Switching materials is as easy as swapping the build platform and

cartridge. The combination of small footprint, simple workflow, and low price make desktop SLA

printers well-suited for both dental labs and practices.

SLA printers offer large build volumes and a wide range of materials. From left to right: crown and bridge models,

surgical guides, splints, and orthodontic models.


DIGITAL LIGHT PROCESSING (DLP)

Digital Light Processing operates with the same chemical process as SLA, but uses a digital

projector as a light source to solidify the resin, rather than a laser. DLP printers have a small

footprint, simple workflow, and wide range of material options, but at a substantially higher cost

than desktop SLA printers. DLP parts also tend to show voxel lines—layers formed by small

rectangular bricks due to digital screen—and have a generally less good surface finish.

MATERIAL JETTING

Material jetting (PolyJet and MultiJet Modeling) 3D printers work similarly to inkjet printing, but

instead of jetting drops of ink onto paper, they jet layers of liquid resin onto a build tray and cure

them instantly using light. Material jetting technologies were the most common in the dental

industry a few years ago, but expansion was limited by their high cost and the large size of the

machines. They require extensive post-processing and the surface finish of parts produced with

this technology generally inferior to SLA or DLP. Material jetting systems have high throughput, but

can only be used for a limited range of applications due to the costly, proprietary materials.

COMPARISON OF DENTAL 3D PRINTING TECHNOLOGIES

Sterolithography Digital Light Processing Material Jetting

SLA DLP MJP, PolyJet

Accuracy

Surface Finish

Throughput

Materials

Pros Great value

High accuracy

Wide range of materials

Desktop footprint

Easy to use

High accuracy

Wide range of materials

Desktop footprint

Easy to use

High accuracy

High throughput

Cons Expensive machinery

Small build volume

Expensive machinery

Expensive materials

Limited material options

Large footprint

Costly maintenance

Price Starting at $3,500 Starting at $12,000 Starting at $35,000


How to Evaluate 3D Printing SolutionsACCURACY AND PRECISION

Guaranteeing high-quality final parts is the most important concern for a dental practice or lab.

The three best measures to take to protect yourself from buying inaccurate equipment are:

1. Be skeptical - don’t trust what companies say.

2. Judge accuracy benchmarked on final 3D printed models, not on technical specifications.

3. Order sample parts and judge accuracy and precision for yourself.

Manufacturers may try to confuse prospective customers with misleading statements and technical

specifications. Most commonly, they masquerade layer height, laser spot size, or pixel size as

“accuracy”, even though these specifications do not have a direct impact on accuracy of final parts.

While most companies refer to a single number for accuracy (i.e. 50 microns or 75 microns), these

are typically marketing gimmicks, and most commonly represent the limit of resolution of the printer.

Fundamentally, a printer’s accuracy and precision are defined by how well-calibrated all of its

systems are, so a system can only be judged on its final printed parts. Desktop optical scanning

allows for the comparison of the organic shapes of printed dental prosthetics to the .STL that was

sent to the machine. Scans of printed models are scored in terms of the percent of points within a

given distance from the nominal point on the .STL (i.e. 80% of points within ±50 microns).

Accuracy study of a 3D printed splint (left) and surgical guide (right). Dental 3D printers can produce high-quality cus-

tom products and appliances with superior fit and repeatable results.

Always demand accuracy studies with real scan data of printed parts. Even better, ask for a free

sample part or a custom sample of your own design that you can measure yourself against the

original design, and judge the quality using free comparison software.

https://formlabs.com/request-sample-part/


http://www.gom.com/3d-software/gom-inspect.html


EASE OF USE AND RELIABILITY

How easy a 3D printer is to use, and how reliable it will be in production are also important

considerations. After all, your team is going to have to learn how to use the equipment and maintain

it on a daily basis. Try to get a sense of the learning curve that will come with a new 3D printer by

watching videos online, visiting a trade show, contacting sales, or asking colleagues about their

experience.

Think carefully about the equipment’s setup requirements. Some newer printers are designed

intuitively enough to start printing straight out of the box. Other more complicated machines require

a service technician to be present during setup.

Pay close attention to the types of everyday interactions and maintenance the printer will need

once it is up and running. Automatic resin dispensing, available on select SLA machines and

material jetting printers, can make a big difference in keeping a clean, low-maintenance production

environment, and also allows for quick switching between materials.

Early 3D printers had an infamous reputation for spending half of their life in service, with many

failed prints even when they were online. Fortunately, the latest generation of printers are pushing

beyond this. For example, users of the Form 2 3D printer reported a success rate of over 95%

on millions of prints across tens of thousands of machines. Dig deep into published reliability

information, and make sure that a manufacturer has appropriate warranties and service offerings to

ensure you’ll be taken care of if service is needed.

COSTS AND RETURN ON INVESTMENT

Adopting new technology needs to simply make sense for your business. Remember to consider:

1. Upfront costs, including not just the machine cost, but also training and setup

for larger-format machines, as well as, potentially, software.

2. Running costs, best estimated with per-unit material costs.

3. Servicing and maintenance costs, which can sometimes include compulsory

service contracts and cost as much as 20% of the upfront cost of the printer annually.

All of these factors directly impact on how fast you can make a return on investing in 3D printing

technology. The good news is that with smaller-format, low-cost machines that offer high-output

quality, it’s now possible for dental labs and practices to achieve positive ROI within months.


MATERIALS AND APPLICATIONS

Professional 3D printers are some of the most versatile tools found today in dental labs and

practices, and the key to their versatility is dedicated materials.

The material selection varies by printer model. Some basic 3D printers can only produce

orthodontic models, while more advanced models can manufacture highly accurate crown and

bridge models, surgical guides, castable/pressable restorations, and long-term and biocompatible

dental products like splints, retainers, or dentures.

Some 3D printers work only with proprietary materials, which means your options are limited to

the offerings of the printer manufacturer. Others have an open system, meaning that they can use

materials made by third party manufacturers. In the case of these third party materials, it’s important

to make sure that the results achieve clinically acceptable quality and accuracy.

Manufacturers release new materials on a regular basis, so there’s a good chance that the

printer you buy today will become capable of creating an increasing variety of dental products

in the near future.

Crown and bridge models 3D printed on a Formlabs Form 2 desktop SLA printer.


THROUGHPUT AND SCALABILITY

Transitioning to digital dentistry should be a gradual process, starting with a single application,

and scaling up to multiple applications and workflows step by step.

The number of dental products a 3D printer can produce depends highly on the specific model

and the application. For example, a DLP printer’s projector exposes layers to light all at once,

whereas in SLA printers, the laser has to draw out each part. This leads to an increase in speed

for large, fully dense prints. However, the resolution of the projector limits the build volume,

so the overall throughput is similar. Inquire with the manufacturer for specific data on multiple

applications and scenarios.

THROUGHPUT AND COST OF DENTAL PRODUCTS with 3D Printing on a Form 2 Desktop SLA 3D Printer

Printing on the Form 2

Quad w/ Dies

Full Arch w/ Dies

Quarter Arch Surgical Guide

Full Arch Surgical Guide

Splint / Retainer

Full Arch Orthodontic Model

Number of Parts Per Build

16 quadrants and dies

4 arches and dies

18 guides 12 guides 7 splints 9 arches

Time 2 quads / 3 hours

16 quads / 8.5 hours

2 arches / 5.5 hours

4 arches / 8 hours

1 guide / 1.5 hours

18 guides / 4.5 hours

1 guide / 1.5 hours

8 guides / 7 hours

1 splint / 50 minutes

7 splints / 2 hours

1 arch / 2.5 hours

9 arches / 7.5 hours

Cost Per Part

$1.5 / quadrant

$3 – 5 / arch $2 – 3 / guide

$3 – 5 / guide

$4 – 6 / splint

$1.5 – 3.5 / arch

Production with multi-machine print cells often reduces upfront costs compared to larger-format

machines. By buying one low-cost machine at first, businesses can test out production methods

before ultimately scaling up production with demand. This provides the opportunity to pay for

production only when it is needed, rather than making large long-term investments in a rapidly-

evolving market.

Print cells reduce risk through redundancy. If one machine needs servicing, production can be

balanced across the rest of the print cell.

Multi-machine print cells allow 3D printing for multiple different applications in parallel, balancing production needs

and lowering risk through redundancy.

Get Started with Digital Dentistry and 3D Printing

With thousands of dental practices and dental labs already adopting digital dentistry, there’s

never been a better time to start exploring how to take advantage of new technology in your

business. While a few years ago 3D printers were only affordable to the largest dental labs,

now they are a common sight in labs and practices of any size.

Consider the factors discussed above and the needs of your lab and practice—different

solutions might suit some business better than others. Digital dentistry is developing rapidly,

and new desktop solutions can produce dental products with similar or even better quality and

accuracy traditional large-format 3D printers. Make sure to do your research, evaluate actual

parts, and avoid paying a hefty premium.



Documents

FORMLABS WHITE PAPER: Introduction to Digital …...FORMLABS WHITE PAPER: Introduction to Digital Dentistry and 3D Printer Buyer’s Guide 6 The digital dentistry workflow can move